package com.scut.miaosha.redis;

import com.alibaba.fastjson.JSON;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;


@Service
public class RedisService {
    @Autowired
    JedisPool jedisPool;

    /*
    获得当个对象
     */
    public <T> T get(KeyPrefix prefix,String key , Class<T> clazz)
    {
        Jedis jedis = null;
        try{
            jedis = jedisPool.getResource();
            //生成真正的key
            String realKey = prefix.getPrefix() + key;
            String str = jedis.get(realKey);
            T t = stringToBean(str , clazz);
            return t;
        }finally {
            returnToPool(jedis);
        }
    }

    /*
    设置当个对象
     */
    public <T> boolean set(KeyPrefix prefix, String key, T value)
    {
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String str = beanToString(value);
            if(str == null || str.length() <= 0)
            {
                return false;
            }
            String realKey = prefix.getPrefix() + key;
            int seconds = prefix.expireSeconds();
            if(seconds <= 0)
            {
                jedis.set(realKey , str);
            }else{
                jedis.setex(realKey,seconds,str);
            }
            return true;
        }
        finally {
            returnToPool(jedis);
        }
    }

    /*
    增加值
     */
    public <T> Long incr(KeyPrefix prefix , String key){
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String realKey = prefix.getPrefix() + key;
            return jedis.incr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    /*
    减少值
     */
    public <T> Long decr(KeyPrefix prefix , String key){
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String realKey = prefix.getPrefix() + key;
            return jedis.decr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }


    //删除
    public  boolean delete(KeyPrefix prefix, String key)
    {
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String realKey = prefix.getPrefix() + key;
            long ret =  jedis.del(realKey);
            return ret > 0 ;
        }finally {
            returnToPool(jedis);
        }
    }

    /*
    判断key是否存在
     */
    public <T> boolean exists(KeyPrefix prefix, String key)
    {
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String realKey = prefix.getPrefix() + key;
             return jedis.exists(realKey);
        }finally {
            returnToPool(jedis);
        }
    }



    public static <T> String beanToString(T value) {
        if(value == null)
        {
            return null;
        }
        Class<?> clazz = value.getClass();
        //需要单独处理的类型
        if(clazz == int.class || clazz == Integer.class) {
            return ""+value;
        }else if(clazz == String.class) {
            return (String) value;
        }else if(clazz == long.class || clazz == Long.class) {
            return ""+value;
        }
        return JSON.toJSONString(value);
    }

    public  static  <T> T stringToBean(String str , Class<T> clazz) {
        if(str == null || str.length() <= 0 || clazz == null)
        {
            return null;
        }
        if(clazz == int.class || clazz == Integer.class) {
            return (T)Integer.valueOf(str);
        }else if(clazz == String.class) {
            return (T)str;
        }else if(clazz == long.class || clazz == Long.class) {
            return (T)Long.valueOf(str);
        }
        return JSON.toJavaObject(JSON.parseObject(str), clazz);
    }

    public void returnToPool(Jedis jedis)
    {
        if(jedis != null)
        {
            jedis.close();
        }
    }

}
